Tutorial by Examples: er

Default values for placeholders

If you want to have a placeholder that may be omitted, you can give it a default value: Using YAML: # app/config/routing.yml blog_list: path: /blog/{page} defaults: { _controller: AppBundle:Blog:list, page: 1 } requirements: page: '\d+' Using Annotations: // src/...

symfony • Routing

A simple controller class

// src/AppBundle/Controller/HelloWorldController.php namespace AppBundle\Controller; use Symfony\Component\HttpFoundation\Response; class HelloWorldController { public function helloWorldAction() { return new Response( '<html><body>Hello World!<...

symfony • Controllers

Rendering a Twig template

Most of the time, you will want to render HTML responses from a template instead of hard-coding the HTML in your controller. Also, your templates will not be static but will contain placeholders for application data. By default Symfony comes with Twig, a powerful templating language. In order to us...

symfony • Controllers

Using data from the Request object

If you need to access the Request object (for instance to read the query parameters, to read an HTTP header or to process an uploaded file), you can receive the request as a method argument by adding a type-hinted argument: use Symfony\Component\HttpFoundation\Request; public function indexActio...

symfony • Controllers

dispatcher-servlet.xml

This is the important configuration file where we need to specify the ViewResolver and View components. The context:component-scan element defines the base-package where DispatcherServlet will search the controller class. Here, the InternalResourceViewResolver class is used for the ViewResolver. ...

spring • Understanding the dispatcher-servlet.xml

dispatcher servlet configuration in web.xml

In this XML file, we are specifying the servlet class DispatcherServlet that acts as the front controller in Spring Web MVC. All the incoming request for the HTML file will be forwarded to the DispatcherServlet. <?xml version="1.0" encoding="UTF-8"?> <web-app version...

spring • Understanding the dispatcher-servlet.xml

CASE in ORDER BY clause to sort records by lowest value of 2 columns

Imagine that you need sort records by lowest value of either one of two columns. Some databases could use a non-aggregated MIN() or LEAST() function for this (... ORDER BY MIN(Date1, Date2)), but in standard SQL, you have to use a CASE expression. The CASE expression in the query below looks at th...

SQL • CASE

Adding the axWindowsMediaPlayer

Right-click on the Toolbox, then click "Choose Items". Select the COM Components tab, and then check Windows Media Player. axWindowsMediaPlayer will be added to Toolbox. Select this checkbox to use axWindowsMediaPlayer Then you can use axWindowsMediaPlayer :)

Visual Basic .NET Language • Using axWindowsMediaPlayer in VB.Net

Getting a query string parameter

Lets say we want to build a paginated list of products, where the number of the page is passed as a query string parameter. For instance, to fetch the 3rd page, you'd go to: http://example.com/products?page=3 The raw HTTP request would look something like this: GET /products?page=3 HTTP/1.1 Ho...

symfony • The Request

Integration and Differentiation

Sympy is made for symbolic math, so let's have a look at some basic integration and differentiation. from sympy import symbols, sqrt, exp, diff, integrate, pprint x, y = symbols(...

sympy • Getting started with sympy

Ternary Operator (Shorthand If-Then-Else) & Null-Coalescing Operator

The ternary operator (?:) Support for the extended ternary operator was added in Twig 1.12.0. {{ foo ? 'yes' : 'no' }} Evaluates: if foo echo yes else echo no {{ foo ?: 'no' }} or {{ foo ? foo : 'no' }} Evaluates: if foo echo it, else echo no {{ foo ? 'yes' }} or {{ f...

twig • Basic template syntax

API-KEY base request authentication

You can use django rest framework permission classes to check request headers and authenticate user requests Define your secret_key on project settings API_KEY_SECRET = 'secret_value' note: a good practice is to use environment variables to store this secret value. Define a permission ...

django-rest-framework • Authentication

Firebase Query Example

private void loadData(){ DatabaseReference dbRef = FirebaseDatabase.getInstance().getReference(); Query dataQuery = dbRef.child("chat").orderByChild("id").equalTo("user1"); dataQuery.addListenerForSingleValueEvent(new ValueEventListener() { ...

firebase-database • Firebase Query

Installing and configuring Windows installer

Detailed instructions on getting windows-installer set up or installed.

windows-installer • Getting started with windows-installer

What is the difference between customErrors and httpErrors?

Both are used to define error handling for a website, but different software refers to different config elements. customErrors are a legacy (backwards compatable) element, used by Visual Studio Development Server (aka. VSDS or Cassini). httpErrors are the new element which is only used by IIS7. T...

ASP.NET • web.config > system.webServer/httpErrors & system.web/customErrors sections

Testing Xpaths in browser console

A quick way to test your xpath is in your browser developer tool console. Format is $x('//insert xpath here') $ - specifies it is a selector. x - specifies it is using xpaths Example: $x("//button[text() ='Submit']") When this command is entered it will return all occurrences...

xpath • Getting started with xpath

How to get selected records from another table (using TCA group field)

Example of a TCA field configuration where you can select records from a table 'my_topfeatures' => array( 'label' => 'Select Topfeatures', 'config' => array( 'type' => 'group', 'internal_type' => 'db', 'size' => '4', ...

typo3 • Database Query DataProcessor - Examples

IF, TRY and others are expressions, not statements

In Kotlin, if, try and others are expressions (so they do return a value) rather than (void) statements. So, for example, Kotlin does not have Java's ternary Elvis Operator, but you can write something like this: val i = if (someBoolean) 33 else 42 Even more unfamiliar, but equally expressive, ...

Kotlin • Kotlin for Java Developers

Generate a Scheduled Newsletter

Create the Newsletter model: rails g model Newsletter name:string email:string subl app/models/newsletter.rb validates :name, presence: true validates :email, presence: true Create the Newsletter controller: rails g controller Newsletters create class NewslettersCont...

Ruby on Rails • ActionMailer

countdown timer using moment.js

HTML <div class="countdown"></div> JS var duration = moment.duration({ 'minutes': 5, 'seconds': 00 }); var timestamp = new Date(0, 0, 0, 2, 10, 30); var interval = 1; var timer = setInterval(function() { timestamp = new Date(timestamp.getTi...

momentjs • countdown timer in minutes using moment.js